Recently, the researchers revealed that, the Mitochondria, the powerhouse organelles of mammalian and plant cells might have once been parasitic bacteria. The study named as “Phylogenomic Reconstruction Indicates Mitochondrial Ancestor Was an Energy Parasite” was published in the PLOS journal.
The Virginia University researchers have used a special DNA-sequencing method in order to discover the genomes of 18 different bacteria which are believed to characterize as the closest relatives of mitochondria. The researchers team has used an entirely different approach as compared to other studies. In contrast to just simply discovering the genetic structure of contemporary mitochondria (proto-mitochondria), the team decided to look at the pre-mitochondria, which is the last common ancestor of mitochondria and its sister clade (alphaproteobacteria).
Mitochondria guarantee the cell is provided with power, through generation of adenosine triphosphate (ATP). Often named the “energy currency of the cell,” ATP is used within cells to transport chemical energy and assist a host of metabolic reactions.
Certainly, the mitochondria came into existence around 2 billion years ago. They are serving as one of the major evolutionary changes to the nucleus-harboring cell. Though, the mitochondrion exact origin remains the mystery and has long puzzled contemporary researchers.
According to the former theories, there was an instant symbiosis between the bacteria, from which mitochondria evolved, and the host cell, however, the new study proposed that the relationship was not always a mutually beneficial one.
“We believe the relationship likely was antagonistic that the bacteria were parasitic and only later became beneficial to the host cell by switching the direction of the ATP transport.”
Martin Wu, University of Virginia biologist stated that, the sequences reveal that mitochondria likely derived from a parasitic type of bacteria that actually “stole energy,” extracting molecules of ATP using a special ATP/ADP translocase transporter.
Wu stated, we concluded that the level of biodiversity seen throughout the ages would not have been possible without mitochondria.
Researchers also discovered a number of human genes that originated from mitochondria. According to Wu and colleagues, further investigation of these genes could lead to a better understanding of mitochondrial dysfunction, typically seen in a number of age-related pathologies.